diff --git a/news/89.dep b/news/89.dep
new file mode 100644
index 0000000000000000000000000000000000000000..a9d51923d65cf8bbe6576274aa088a295b84b60a
--- /dev/null
+++ b/news/89.dep
@@ -0,0 +1,2 @@
+Update dependencies `pythonfinder`, `python-cfonts`, `pip-shims` and many others.
+Drop dependency `vistir`.
diff --git a/pdm.lock b/pdm.lock
index d93b1a74c2194a81abf4bf546b8153bdb0f85fad..38e2f5cd6c767aa4af5e1f03ed9a2df24366e26d 100644
--- a/pdm.lock
+++ b/pdm.lock
@@ -35,7 +35,7 @@ summary = "A decorator for caching properties in classes."
 [[package]]
 name = "click"
 sections = ["default", "dev", "doc"]
-version = "7.0"
+version = "7.1.1"
 marker = "python_version >= \"2.7\""
 summary = "Composable command line interface toolkit"
 
@@ -49,20 +49,10 @@ summary = "Cross-platform colored terminal text."
 [[package]]
 name = "coverage"
 sections = ["dev"]
-version = "4.4.2"
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
+version = "5.0.4"
+marker = "python_version >= \"2.7\" and python_version < \"4.0\" and python_version not in \"3.0, 3.1, 3.2, 3.3, 3.4\""
 summary = "Code coverage measurement for Python"
 
-[[package]]
-name = "crayons"
-sections = ["default"]
-version = "0.3.0"
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
-summary = "TextUI colors for Python."
-
-[package.dependencies]
-colorama = "*"
-
 [[package]]
 name = "cursor"
 sections = ["default"]
@@ -95,32 +85,22 @@ summary = "Clean single-source support for Python 3 and 2"
 [[package]]
 name = "halo"
 sections = ["default"]
-version = "0.0.28"
+version = "0.0.29"
 summary = "Beautiful terminal spinners in Python"
 
 [package.dependencies]
-log-symbols = ">=0.0.13"
-spinners = ">=0.0.23"
+log-symbols = ">=0.0.14"
+spinners = ">=0.0.24"
 cursor = ">=1.2.0"
 termcolor = ">=1.1.0"
 colorama = ">=0.3.9"
 six = ">=1.12.0"
 
-[[package]]
-name = "importlib-metadata"
-sections = ["dev"]
-version = "1.5.0"
-marker = "python_version >= \"3.5\" and python_version < \"3.8\""
-summary = "Read metadata from Python packages"
-
-[package.dependencies]
-zipp = ">=0.5"
-
 [[package]]
 name = "incremental"
 sections = ["dev"]
 version = "17.5.0"
-summary = ""
+summary = "UNKNOWN"
 
 [[package]]
 name = "jinja2"
@@ -139,6 +119,10 @@ version = "2.6.1"
 marker = "python_version >= \"3.5\""
 summary = "Python LiveReload is an awesome tool for web developers"
 
+[package.dependencies]
+tornado = "*"
+six = "*"
+
 [[package]]
 name = "log-symbols"
 sections = ["default"]
@@ -189,6 +173,9 @@ sections = ["doc"]
 version = "0.5.1"
 summary = "This is an extension to Python-Markdown which provides an \"include\" function, similar to that found in LaTeX (and also the C pre-processor and Fortran). I originally wrote it for my FORD Fortran auto-documentation generator."
 
+[package.dependencies]
+markdown = "*"
+
 [[package]]
 name = "MarkupSafe"
 sections = ["dev", "doc"]
@@ -238,10 +225,13 @@ version = "3.4.5"
 marker = "python_version >= \"3.5\""
 summary = "Natural Language Toolkit"
 
+[package.dependencies]
+six = "*"
+
 [[package]]
 name = "packaging"
 sections = ["default", "dev"]
-version = "20.1"
+version = "20.3"
 marker = "python_version >= \"2.7\""
 summary = "Core utilities for Python packages"
 
@@ -259,7 +249,7 @@ summary = "The PyPA recommended tool for installing Python packages."
 [[package]]
 name = "pip-shims"
 sections = ["default"]
-version = "0.5.0"
+version = "0.5.1"
 marker = "python_version >= \"2.7\" and python_full_version not in \"3.0.0, 3.1.0, 3.2.0, 3.3.0, 3.4.0\""
 summary = "Compatibility shims for pip versions 8 thru current."
 
@@ -277,9 +267,6 @@ version = "0.13.1"
 marker = "python_version >= \"3.5\""
 summary = "plugin and hook calling mechanisms for python"
 
-[package.dependencies]
-importlib-metadata = {marker = "python_version < \"3.8\"", version = ">=0.12"}
-
 [[package]]
 name = "py"
 sections = ["dev"]
@@ -290,8 +277,8 @@ summary = "library with cross-python path, ini-parsing, io, code, log facilities
 [[package]]
 name = "Pygments"
 sections = ["doc"]
-version = "2.5.2"
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3, 3.4\""
+version = "2.6.1"
+marker = "python_version >= \"3.5\""
 summary = "Pygments is a syntax highlighting package written in Python."
 
 [[package]]
@@ -301,6 +288,9 @@ version = "6.3"
 marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3, 3.4\""
 summary = "Extension pack for Python Markdown."
 
+[package.dependencies]
+Markdown = ">=3.2"
+
 [[package]]
 name = "pyparsing"
 sections = ["default", "dev"]
@@ -311,7 +301,7 @@ summary = "Python parsing module"
 [[package]]
 name = "pytest"
 sections = ["dev"]
-version = "5.3.5"
+version = "5.4.1"
 marker = "python_version >= \"3.5\""
 summary = "pytest: simple powerful testing with Python"
 
@@ -322,7 +312,6 @@ attrs = ">=17.4.0"
 more-itertools = ">=4.0.0"
 pluggy = "<1.0,>=0.12"
 wcwidth = "*"
-importlib-metadata = {marker = "python_version < \"3.8\"", version = ">=0.12"}
 atomicwrites = {marker = "sys_platform == \"win32\"", version = ">=1.0"}
 colorama = {marker = "sys_platform == \"win32\"", version = "*"}
 
@@ -357,12 +346,6 @@ summary = "Thin-wrapper around the mock package for easier use with py.test"
 [package.dependencies]
 pytest = ">=2.7"
 
-[[package]]
-name = "pytest-sugar"
-sections = ["dev"]
-version = "0.9.2"
-summary = "pytest-sugar is a plugin for pytest that changes the default look and feel of pytest (e.g. progressbar, show tests that fail instantly)."
-
 [[package]]
 name = "pytest-xdist"
 sections = ["dev"]
@@ -379,7 +362,7 @@ six = "*"
 [[package]]
 name = "python-cfonts"
 sections = ["default"]
-version = "1.1.0"
+version = "1.2.0"
 marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3, 3.4\""
 summary = "Sexy fonts for the console"
 
@@ -389,7 +372,7 @@ colorama = "*"
 [[package]]
 name = "pythonfinder"
 sections = ["default"]
-version = "1.2.1"
+version = "1.2.2"
 marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
 summary = "A cross-platform python discovery tool to help locate python on any system."
 
@@ -397,22 +380,20 @@ summary = "A cross-platform python discovery tool to help locate python on any s
 attrs = "*"
 cached-property = "*"
 click = "*"
-crayons = "*"
 six = "*"
 packaging = "*"
-vistir = {extras = ["spinner"], version = ">=0.4"}
 
 [[package]]
 name = "PyYAML"
 sections = ["doc"]
-version = "5.3"
+version = "5.3.1"
 marker = "python_version >= \"3.5\""
 summary = "YAML parser and emitter for Python"
 
 [[package]]
 name = "setuptools"
 sections = ["default", "doc"]
-version = "45.2.0"
+version = "46.1.3"
 marker = "python_version >= \"3.5\""
 summary = "Easily download, build, install, upgrade, and uninstall Python packages"
 
@@ -426,7 +407,7 @@ summary = "Python 2 and 3 compatibility utilities"
 [[package]]
 name = "spinners"
 sections = ["default"]
-version = "0.0.23"
+version = "0.0.24"
 summary = "Spinners for terminals"
 
 [[package]]
@@ -451,7 +432,7 @@ summary = "Style preserving TOML library"
 [[package]]
 name = "tornado"
 sections = ["doc"]
-version = "6.0.3"
+version = "6.0.4"
 marker = "python_version >= \"3.5\""
 summary = "Tornado is a Python web framework and asynchronous networking library, originally developed at FriendFeed."
 
@@ -467,35 +448,10 @@ incremental = "*"
 jinja2 = "*"
 toml = "*"
 
-[[package]]
-name = "vistir"
-sections = ["default"]
-version = "0.5.0"
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
-summary = "Miscellaneous utilities for dealing with filesystems, paths, projects, subprocesses, and more."
-
-[package.dependencies]
-colorama = "!=0.4.2,>=0.3.4"
-six = "*"
-
-[[package]]
-name = "vistir"
-sections = ["default"]
-version = "0.5.0"
-extras = ["spinner"]
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
-summary = "Miscellaneous utilities for dealing with filesystems, paths, projects, subprocesses, and more."
-
-[package.dependencies]
-colorama = "!=0.4.2,>=0.3.4"
-six = "*"
-yaspin = "*"
-vistir = {marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\"", version = "==0.5.0"}
-
 [[package]]
 name = "wcwidth"
 sections = ["dev"]
-version = "0.1.8"
+version = "0.1.9"
 marker = "python_version >= \"3.5\""
 summary = "Measures number of Terminal column cells of wide-character codes"
 
@@ -506,86 +462,67 @@ version = "0.34.2"
 marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3, 3.4\""
 summary = "A built-package format for Python"
 
-[[package]]
-name = "yaspin"
-sections = ["default"]
-version = "0.16.0"
-marker = "python_version >= \"2.7\" and python_version not in \"3.0, 3.1, 3.2, 3.3\""
-summary = "Yet Another Terminal Spinner"
-
-[[package]]
-name = "zipp"
-sections = ["dev"]
-version = "3.0.0"
-marker = "python_version >= \"3.6\" and python_version < \"3.8\""
-summary = "Backport of pathlib-compatible object wrapper for zip files"
-
 [metadata]
 "apipkg 1.5" = [
-    {file = "apipkg-1.5-py2.py3-none-any.whl", hash = "sha256:58587dd4dc3daefad0487f6d9ae32b4542b185e1c36db6993290e7c41ca2b47c"},
     {file = "apipkg-1.5.tar.gz", hash = "sha256:37228cda29411948b422fae072f57e31d3396d2ee1c9783775980ee9c9990af6"},
+    {file = "apipkg-1.5-py2.py3-none-any.whl", hash = "sha256:58587dd4dc3daefad0487f6d9ae32b4542b185e1c36db6993290e7c41ca2b47c"},
 ]
 "appdirs 1.4.3" = [
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     {file = "appdirs-1.4.3.tar.gz", hash = "sha256:9e5896d1372858f8dd3344faf4e5014d21849c756c8d5701f78f8a103b372d92"},
+    {file = "appdirs-1.4.3-py2.py3-none-any.whl", hash = "sha256:d8b24664561d0d34ddfaec54636d502d7cea6e29c3eaf68f3df6180863e2166e"},
 ]
 "atomicwrites 1.3.0" = [
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+    {file = "atomicwrites-1.3.0-py2.py3-none-any.whl", hash = "sha256:03472c30eb2c5d1ba9227e4c2ca66ab8287fbfbbda3888aa93dc2e28fc6811b4"},
 ]
 "attrs 19.3.0" = [
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+    {file = "attrs-19.3.0-py2.py3-none-any.whl", hash = "sha256:08a96c641c3a74e44eb59afb61a24f2cb9f4d7188748e76ba4bb5edfa3cb7d1c"},
 ]
 "cached-property 1.5.1" = [
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-    {file = "Click-7.0-py2.py3-none-any.whl", hash = "sha256:2335065e6395b9e67ca716de5f7526736bfa6ceead690adf616d925bdc622b13"},
+"click 7.1.1" = [
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 "colorama 0.4.3" = [
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 ]
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-]
-"crayons 0.3.0" = [
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-    {file = "PyYAML-5.3-cp37-cp37m-win_amd64.whl", hash = "sha256:1cf708e2ac57f3aabc87405f04b86354f66799c8e62c28c5fc5f88b5521b2dbf"},
-    {file = "PyYAML-5.3-cp38-cp38-win32.whl", hash = "sha256:70024e02197337533eef7b85b068212420f950319cc8c580261963aefc75f811"},
-    {file = "PyYAML-5.3-cp38-cp38-win_amd64.whl", hash = "sha256:cb1f2f5e426dc9f07a7681419fe39cee823bb74f723f36f70399123f439e9b20"},
-]
-"setuptools 45.2.0" = [
-    {file = "setuptools-45.2.0.zip", hash = "sha256:89c6e6011ec2f6d57d43a3f9296c4ef022c2cbf49bab26b407fe67992ae3397f"},
-    {file = "setuptools-45.2.0-py3-none-any.whl", hash = "sha256:316484eebff54cc18f322dea09ed031b7e3eb00811b19dcedb09bc09bba7d93d"},
+"python-cfonts 1.2.0" = [
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+    {file = "python_cfonts-1.2.0-py2.py3-none-any.whl", hash = "sha256:b5f0657fee522afc294a2311738cbfaaebcc11b703d7c96ce31ae064b3ac43bd"},
+]
+"pythonfinder 1.2.2" = [
+    {file = "pythonfinder-1.2.2.tar.gz", hash = "sha256:6cab0773cb811e946b4eb76b1f2e4faf7c657c848f0e0682f6f8291cd1091a2a"},
+    {file = "pythonfinder-1.2.2-py2.py3-none-any.whl", hash = "sha256:73cf4cdcb4a6754fd29a5b96120679bde7c1f587bd1fb63b748d3a5fef6e4090"},
+]
+"pyyaml 5.3.1" = [
+    {file = "PyYAML-5.3.1.tar.gz", hash = "sha256:b8eac752c5e14d3eca0e6dd9199cd627518cb5ec06add0de9d32baeee6fe645d"},
+    {file = "PyYAML-5.3.1-cp27-cp27m-win32.whl", hash = "sha256:74809a57b329d6cc0fdccee6318f44b9b8649961fa73144a98735b0aaf029f1f"},
+    {file = "PyYAML-5.3.1-cp27-cp27m-win_amd64.whl", hash = "sha256:240097ff019d7c70a4922b6869d8a86407758333f02203e0fc6ff79c5dcede76"},
+    {file = "PyYAML-5.3.1-cp35-cp35m-win32.whl", hash = "sha256:4f4b913ca1a7319b33cfb1369e91e50354d6f07a135f3b901aca02aa95940bd2"},
+    {file = "PyYAML-5.3.1-cp35-cp35m-win_amd64.whl", hash = "sha256:cc8955cfbfc7a115fa81d85284ee61147059a753344bc51098f3ccd69b0d7e0c"},
+    {file = "PyYAML-5.3.1-cp36-cp36m-win32.whl", hash = "sha256:7739fc0fa8205b3ee8808aea45e968bc90082c10aef6ea95e855e10abf4a37b2"},
+    {file = "PyYAML-5.3.1-cp36-cp36m-win_amd64.whl", hash = "sha256:69f00dca373f240f842b2931fb2c7e14ddbacd1397d57157a9b005a6a9942648"},
+    {file = "PyYAML-5.3.1-cp37-cp37m-win32.whl", hash = "sha256:d13155f591e6fcc1ec3b30685d50bf0711574e2c0dfffd7644babf8b5102ca1a"},
+    {file = "PyYAML-5.3.1-cp37-cp37m-win_amd64.whl", hash = "sha256:73f099454b799e05e5ab51423c7bcf361c58d3206fa7b0d555426b1f4d9a3eaf"},
+    {file = "PyYAML-5.3.1-cp38-cp38-win32.whl", hash = "sha256:06a0d7ba600ce0b2d2fe2e78453a470b5a6e000a985dd4a4e54e436cc36b0e97"},
+    {file = "PyYAML-5.3.1-cp38-cp38-win_amd64.whl", hash = "sha256:95f71d2af0ff4227885f7a6605c37fd53d3a106fcab511b8860ecca9fcf400ee"},
+]
+"setuptools 46.1.3" = [
+    {file = "setuptools-46.1.3.zip", hash = "sha256:795e0475ba6cd7fa082b1ee6e90d552209995627a2a227a47c6ea93282f4bfb1"},
+    {file = "setuptools-46.1.3-py3-none-any.whl", hash = "sha256:4fe404eec2738c20ab5841fa2d791902d2a645f32318a7850ef26f8d7215a8ee"},
 ]
 "six 1.14.0" = [
     {file = "six-1.14.0.tar.gz", hash = "sha256:236bdbdce46e6e6a3d61a337c0f8b763ca1e8717c03b369e87a7ec7ce1319c0a"},
     {file = "six-1.14.0-py2.py3-none-any.whl", hash = "sha256:8f3cd2e254d8f793e7f3d6d9df77b92252b52637291d0f0da013c76ea2724b6c"},
 ]
-"spinners 0.0.23" = [
-    {file = "spinners-0.0.23.tar.gz", hash = "sha256:f396fea1ee00c0622988d7d2bf2895d26dd6f70850ca2ce94eaca52ca4873560"},
+"spinners 0.0.24" = [
+    {file = "spinners-0.0.24.tar.gz", hash = "sha256:1eb6aeb4781d72ab42ed8a01dcf20f3002bf50740d7154d12fb8c9769bf9e27f"},
+    {file = "spinners-0.0.24-py3-none-any.whl", hash = "sha256:2fa30d0b72c9650ad12bbe031c9943b8d441e41b4f5602b0ec977a19f3290e98"},
 ]
 "termcolor 1.1.0" = [
     {file = "termcolor-1.1.0.tar.gz", hash = "sha256:1d6d69ce66211143803fbc56652b41d73b4a400a2891d7bf7a1cdf4c02de613b"},
 ]
 "toml 0.10.0" = [
-    {file = "toml-0.10.0-py2.py3-none-any.whl", hash = "sha256:235682dd292d5899d361a811df37e04a8828a5b1da3115886b73cf81ebc9100e"},
     {file = "toml-0.10.0.tar.gz", hash = "sha256:229f81c57791a41d65e399fc06bf0848bab550a9dfd5ed66df18ce5f05e73d5c"},
+    {file = "toml-0.10.0-py2.py3-none-any.whl", hash = "sha256:235682dd292d5899d361a811df37e04a8828a5b1da3115886b73cf81ebc9100e"},
 ]
 "tomlkit 0.5.11" = [
     {file = "tomlkit-0.5.11.tar.gz", hash = "sha256:f044eda25647882e5ef22b43a1688fb6ab12af2fc50e8456cdfc751c873101cf"},
     {file = "tomlkit-0.5.11-py2.py3-none-any.whl", hash = "sha256:4e1bd6c9197d984528f9ff0cc9db667c317d8881288db50db20eeeb0f6b0380b"},
 ]
-"tornado 6.0.3" = [
-    {file = "tornado-6.0.3.tar.gz", hash = "sha256:c845db36ba616912074c5b1ee897f8e0124df269468f25e4fe21fe72f6edd7a9"},
-    {file = "tornado-6.0.3-cp35-cp35m-win32.whl", hash = "sha256:c9399267c926a4e7c418baa5cbe91c7d1cf362d505a1ef898fde44a07c9dd8a5"},
-    {file = "tornado-6.0.3-cp35-cp35m-win_amd64.whl", hash = "sha256:398e0d35e086ba38a0427c3b37f4337327231942e731edaa6e9fd1865bbd6f60"},
-    {file = "tornado-6.0.3-cp36-cp36m-win32.whl", hash = "sha256:4e73ef678b1a859f0cb29e1d895526a20ea64b5ffd510a2307b5998c7df24281"},
-    {file = "tornado-6.0.3-cp36-cp36m-win_amd64.whl", hash = "sha256:349884248c36801afa19e342a77cc4458caca694b0eda633f5878e458a44cb2c"},
-    {file = "tornado-6.0.3-cp37-cp37m-win32.whl", hash = "sha256:559bce3d31484b665259f50cd94c5c28b961b09315ccd838f284687245f416e5"},
-    {file = "tornado-6.0.3-cp37-cp37m-win_amd64.whl", hash = "sha256:abbe53a39734ef4aba061fca54e30c6b4639d3e1f59653f0da37a0003de148c7"},
+"tornado 6.0.4" = [
+    {file = "tornado-6.0.4.tar.gz", hash = "sha256:0fe2d45ba43b00a41cd73f8be321a44936dc1aba233dee979f17a042b83eb6dc"},
+    {file = "tornado-6.0.4-cp35-cp35m-win32.whl", hash = "sha256:5217e601700f24e966ddab689f90b7ea4bd91ff3357c3600fa1045e26d68e55d"},
+    {file = "tornado-6.0.4-cp35-cp35m-win_amd64.whl", hash = "sha256:c98232a3ac391f5faea6821b53db8db461157baa788f5d6222a193e9456e1740"},
+    {file = "tornado-6.0.4-cp36-cp36m-win32.whl", hash = "sha256:5f6a07e62e799be5d2330e68d808c8ac41d4a259b9cea61da4101b83cb5dc673"},
+    {file = "tornado-6.0.4-cp36-cp36m-win_amd64.whl", hash = "sha256:c952975c8ba74f546ae6de2e226ab3cc3cc11ae47baf607459a6728585bb542a"},
+    {file = "tornado-6.0.4-cp37-cp37m-win32.whl", hash = "sha256:2c027eb2a393d964b22b5c154d1a23a5f8727db6fda837118a776b29e2b8ebc6"},
+    {file = "tornado-6.0.4-cp37-cp37m-win_amd64.whl", hash = "sha256:5618f72e947533832cbc3dec54e1dffc1747a5cb17d1fd91577ed14fa0dc081b"},
+    {file = "tornado-6.0.4-cp38-cp38-win32.whl", hash = "sha256:22aed82c2ea340c3771e3babc5ef220272f6fd06b5108a53b4976d0d722bcd52"},
+    {file = "tornado-6.0.4-cp38-cp38-win_amd64.whl", hash = "sha256:c58d56003daf1b616336781b26d184023ea4af13ae143d9dda65e31e534940b9"},
 ]
 "towncrier 19.2.0" = [
-    {file = "towncrier-19.2.0-py2.py3-none-any.whl", hash = "sha256:de19da8b8cb44f18ea7ed3a3823087d2af8fcf497151bb9fd1e1b092ff56ed8d"},
     {file = "towncrier-19.2.0.tar.gz", hash = "sha256:48251a1ae66d2cf7e6fa5552016386831b3e12bb3b2d08eb70374508c17a8196"},
+    {file = "towncrier-19.2.0-py2.py3-none-any.whl", hash = "sha256:de19da8b8cb44f18ea7ed3a3823087d2af8fcf497151bb9fd1e1b092ff56ed8d"},
 ]
-"vistir 0.5.0" = [
-    {file = "vistir-0.5.0-py2.py3-none-any.whl", hash = "sha256:e47afdec8baf35032a8d17116765f751ecd2f2146d47e5af457c5de1fe5a334e"},
-    {file = "vistir-0.5.0.tar.gz", hash = "sha256:33f8e905d40a77276b3d5310c8b57c1479a4e46930042b4894fcf7ed60ad76c4"},
-]
-"vistir[spinner] 0.5.0" = [
-    {file = "vistir-0.5.0-py2.py3-none-any.whl", hash = "sha256:e47afdec8baf35032a8d17116765f751ecd2f2146d47e5af457c5de1fe5a334e"},
-    {file = "vistir-0.5.0.tar.gz", hash = "sha256:33f8e905d40a77276b3d5310c8b57c1479a4e46930042b4894fcf7ed60ad76c4"},
-]
-"wcwidth 0.1.8" = [
-    {file = "wcwidth-0.1.8-py2.py3-none-any.whl", hash = "sha256:8fd29383f539be45b20bd4df0dc29c20ba48654a41e661925e612311e9f3c603"},
-    {file = "wcwidth-0.1.8.tar.gz", hash = "sha256:f28b3e8a6483e5d49e7f8949ac1a78314e740333ae305b4ba5defd3e74fb37a8"},
+"wcwidth 0.1.9" = [
+    {file = "wcwidth-0.1.9.tar.gz", hash = "sha256:ee73862862a156bf77ff92b09034fc4825dd3af9cf81bc5b360668d425f3c5f1"},
+    {file = "wcwidth-0.1.9-py2.py3-none-any.whl", hash = "sha256:cafe2186b3c009a04067022ce1dcd79cb38d8d65ee4f4791b8888d6599d1bbe1"},
 ]
 "wheel 0.34.2" = [
-    {file = "wheel-0.34.2-py2.py3-none-any.whl", hash = "sha256:df277cb51e61359aba502208d680f90c0493adec6f0e848af94948778aed386e"},
     {file = "wheel-0.34.2.tar.gz", hash = "sha256:8788e9155fe14f54164c1b9eb0a319d98ef02c160725587ad60f14ddc57b6f96"},
-]
-"yaspin 0.16.0" = [
-    {file = "yaspin-0.16.0-py2.py3-none-any.whl", hash = "sha256:e88bf9c9fe4ac588e3620588aadae655dfc20f1f7460338394ef4693bdc2b800"},
-    {file = "yaspin-0.16.0.tar.gz", hash = "sha256:efca3eb7162e575d3ab2e49743cd9bd1f5ec2adc7d85b9489ab145a3f6460ed4"},
-]
-"zipp 3.0.0" = [
-    {file = "zipp-3.0.0-py3-none-any.whl", hash = "sha256:12248a63bbdf7548f89cb4c7cda4681e537031eda29c02ea29674bc6854460c2"},
-    {file = "zipp-3.0.0.tar.gz", hash = "sha256:7c0f8e91abc0dc07a5068f315c52cb30c66bfbc581e5b50704c8a2f6ebae794a"},
+    {file = "wheel-0.34.2-py2.py3-none-any.whl", hash = "sha256:df277cb51e61359aba502208d680f90c0493adec6f0e848af94948778aed386e"},
 ]
 
 [root]
-content_hash = "md5:3562ef521736c4819cd24da3c3c54235"
+content_hash = "md5:fbac358de4e5b0747e3a27154febb055"
 meta_version = "0.0.1"
diff --git a/pdm/installers.py b/pdm/installers.py
index a41889784543997cc18fc70a286bc60bcc9d5284..3f8b06ee882ed719b2f9598b69483562cf741513 100644
--- a/pdm/installers.py
+++ b/pdm/installers.py
@@ -14,13 +14,13 @@ from distlib.wheel import Wheel
 from pip._internal.utils import logging as pip_logging
 from pip._vendor.pkg_resources import Distribution, EggInfoDistribution, safe_name
 from pip_shims import shims
-from vistir import cd
 
 from pdm.exceptions import InstallationError
 from pdm.iostream import stream
 from pdm.models.candidates import Candidate
 from pdm.models.environment import Environment
 from pdm.models.requirements import parse_requirement, strip_extras
+from pdm.utils import cd
 
 
 def _is_dist_editable(dist: Distribution) -> bool:
diff --git a/pdm/models/caches.py b/pdm/models/caches.py
index 2c345df8391fcf9fdaf5f11228d91798f8232f48..cf972f6719065f643fe9fcd144031ba91f0b4064 100644
--- a/pdm/models/caches.py
+++ b/pdm/models/caches.py
@@ -5,10 +5,10 @@ from typing import TYPE_CHECKING, Any, Dict, Optional
 
 import pip_shims
 from pip._vendor import requests
-from vistir.contextmanagers import open_file
 
 from pdm._types import CandidateInfo
 from pdm.exceptions import CorruptedCacheError
+from pdm.utils import open_file
 
 if TYPE_CHECKING:
     from pdm.models.candidates import Candidate
diff --git a/pdm/models/environment.py b/pdm/models/environment.py
index 735a1a24f177f007ba9bba3cf53dc46f93a88360..fb320cee5b5aba7a38d7b51e63afb7a0e20453b0 100644
--- a/pdm/models/environment.py
+++ b/pdm/models/environment.py
@@ -15,8 +15,6 @@ from pip._vendor import packaging, pkg_resources
 from pip_shims import shims
 from pythonfinder import Finder
 from pythonfinder.environment import PYENV_INSTALLED, PYENV_ROOT
-from vistir.contextmanagers import temp_environ
-from vistir.path import normalize_path
 
 from pdm.exceptions import NoPythonVersion
 from pdm.iostream import stream
@@ -31,6 +29,7 @@ from pdm.utils import (
     get_python_version,
     get_sys_config_paths,
     get_venv_python,
+    temp_environ,
 )
 
 if TYPE_CHECKING:
@@ -181,8 +180,8 @@ class Environment:
 
     def is_local(self, path) -> bool:
         """PEP 582 version of ``is_local()`` function."""
-        return normalize_path(path).startswith(
-            normalize_path(self.packages_path.as_posix())
+        return misc.normalize_path(path).startswith(
+            misc.normalize_path(self.packages_path.as_posix())
         )
 
     def evaluate_marker(self, text: str, extra=None) -> bool:
@@ -356,8 +355,8 @@ class GlobalEnvironment(Environment):
         return paths
 
     def is_local(self, path) -> bool:
-        return normalize_path(path).startswith(
-            normalize_path(self.get_paths()["prefix"])
+        return misc.normalize_path(path).startswith(
+            misc.normalize_path(self.get_paths()["prefix"])
         )
 
     @property
diff --git a/pdm/project/core.py b/pdm/project/core.py
index d8a668161f891eba209e98462e7c73fa327e5145..2bca76dbc56e685a7aa3320e4ce90c067a413d63 100644
--- a/pdm/project/core.py
+++ b/pdm/project/core.py
@@ -11,7 +11,6 @@ import halo
 import tomlkit
 from pip._vendor.pkg_resources import safe_name
 from pip_shims import shims
-from vistir.contextmanagers import atomic_open_for_write
 
 from pdm._types import Source
 from pdm.exceptions import ProjectError
@@ -26,7 +25,12 @@ from pdm.project.config import Config
 from pdm.project.meta import PackageMeta
 from pdm.resolver import BaseProvider, EagerUpdateProvider, ReusePinProvider
 from pdm.resolver.reporters import SpinnerReporter
-from pdm.utils import cached_property, find_project_root, get_venv_python
+from pdm.utils import (
+    atomic_open_for_write,
+    cached_property,
+    find_project_root,
+    get_venv_python,
+)
 
 if TYPE_CHECKING:
     from tomlkit.container import Container
diff --git a/pdm/project/meta.py b/pdm/project/meta.py
index ac1e9936c4a3958b3d2f53fd421ba2bf90b96027..7fefd964b767d678af642abfaf3a331c33be69f7 100644
--- a/pdm/project/meta.py
+++ b/pdm/project/meta.py
@@ -6,11 +6,11 @@ import re
 from typing import TYPE_CHECKING, Dict, List, Union
 
 import setuptools
-import vistir
 from pkg_resources import safe_name
 
 from pdm.exceptions import ProjectError
 from pdm.models.markers import Marker
+from pdm.utils import cd
 
 if TYPE_CHECKING:
     from pdm.project import Project
@@ -148,7 +148,7 @@ class PackageMeta:
         package_data = {"": ["*"]}
         exclude_package_data = {}
 
-        with vistir.cd(self.project.root.as_posix()):
+        with cd(self.project.root.as_posix()):
             if not self.includes:
                 if os.path.isdir("src"):
                     package_dir[""] = "src"
diff --git a/pdm/utils.py b/pdm/utils.py
index 91b187ff3b9f40b4d0ff68343d8d3af413fde903..705b3e99311b10798b8a8a89705a556a0fde792d 100644
--- a/pdm/utils.py
+++ b/pdm/utils.py
@@ -14,10 +14,10 @@ import tempfile
 import urllib.parse as parse
 from contextlib import contextmanager
 from pathlib import Path
-from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Tuple, Union
 
 from distlib.wheel import Wheel
-from pip_shims.shims import InstallCommand, PackageFinder, TargetPython
+from pip_shims.shims import InstallCommand, PackageFinder, TargetPython, url_to_path
 
 from pdm._types import Source
 
@@ -418,3 +418,66 @@ def get_venv_python() -> Optional[str]:
         suffix = ""
         scripts = "bin"
     return os.path.join(venv, scripts, f"python{suffix}")
+
+
+@contextmanager
+def atomic_open_for_write(filename: Union[Path, str], *, encoding: str = "utf-8"):
+    fd, name = tempfile.mkstemp("-atomic-write", "pdm-")
+    try:
+        f = open(fd, "w", encoding=encoding)
+        yield f
+    except Exception:
+        f.close()
+        os.unlink(name)
+        raise
+    else:
+        f.close()
+        try:
+            os.unlink(filename)
+        except OSError:
+            pass
+        os.rename(name, filename)
+
+
+@contextmanager
+def cd(path: str):
+    _old_cwd = os.getcwd()
+    os.chdir(path)
+    try:
+        yield
+    finally:
+        os.chdir(_old_cwd)
+
+
+@contextmanager
+def temp_environ():
+    environ = os.environ.copy()
+    try:
+        yield
+    finally:
+        os.environ.clear()
+        os.environ.update(environ)
+
+
+@contextmanager
+def open_file(url, session=None):
+    if url.startswith("file://"):
+        local_path = url_to_path(url)
+        if os.path.isdir(local_path):
+            raise ValueError("Cannot open directory for read: {}".format(url))
+        else:
+            with open(local_path, "rb") as local_file:
+                yield local_file
+    else:
+        headers = {"Accept-Encoding": "identity"}
+        with session.get(url, headers=headers, stream=True) as resp:
+            try:
+                raw = getattr(resp, "raw", None)
+                result = raw if raw else resp
+                yield result
+            finally:
+                if raw:
+                    conn = getattr(raw, "_connection")
+                    if conn is not None:
+                        conn.close()
+                result.close()
diff --git a/pyproject.toml b/pyproject.toml
index a0ab0e0c9bae308b7b8ac47e9024b5f0a7aae2a0..d87789d50ab5a5044df7807000c5fe4df71fda7d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,7 +39,6 @@ pytest = "*"
 pytest-cov = "*"
 pytest-mock = "*"
 towncrier = "<20.0.0,>=19.2.0"
-pytest-sugar = "<1.0.0,>=0.9.2"
 pytest-xdist = "<2.0.0,>=1.31.0"
 
 [tool.pdm.doc-dependencies]
diff --git a/setup.cfg b/setup.cfg
index 758c431fcaa22ac2fab5730f31d8ecbac2e97c05..689c8e7d20284558cff33d6088ba985fe7a8a4eb 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -46,7 +46,6 @@ known_first_party = pdm
 known_third_party =
     click
     halo
-    vistir
     distlib
     pythonfinder
     pytest
diff --git a/setup_dev.py b/setup_dev.py
index d965804c3cedc71d5818455fdc4bd745d4e4576b..528c741f74f7d187dc4c29550041275fae76cebb 100644
--- a/setup_dev.py
+++ b/setup_dev.py
@@ -28,7 +28,16 @@ def main():
     subprocess.check_call([venv_python.as_posix(), "-m", "pip", "install", "pdm"])
 
     subprocess.check_call(
-        [venv_python.as_posix(), "-m", "pip", "install", "pip", "pip_shims", "-U"]
+        [
+            venv_python.as_posix(),
+            "-m",
+            "pip",
+            "install",
+            "-U",
+            "pip",
+            "pip_shims",
+            "vistir",
+        ]
     )
 
     print("Setup project for development...", flush=True)
diff --git a/tests/cli/test_actions.py b/tests/cli/test_actions.py
index 4ec13cfb71cfa4ea02d5f989c70f324827ddd0c2..b38a9e3129ed19bdf972e33ba1fce22ec1245080 100644
--- a/tests/cli/test_actions.py
+++ b/tests/cli/test_actions.py
@@ -357,7 +357,7 @@ def test_list_dependency_graph(capsys):
     project = Project()
     actions.do_list(project, True)
     content, _ = capsys.readouterr()
-    assert "halo 0.0.28 [ required: <1.0.0,>=0.0.28 ]" in content
+    assert "halo 0.0.29 [ required: <1.0.0,>=0.0.28 ]" in content
     assert "six 1.14.0 [ required: >=1.12.0 ]" in content
 
 
diff --git a/tests/cli/test_cli.py b/tests/cli/test_cli.py
index fa6f043bb21619b00fce46eda603aa2654f27093..f9fca914d7482b01a893e84d0daaf40a9801e238 100644
--- a/tests/cli/test_cli.py
+++ b/tests/cli/test_cli.py
@@ -4,11 +4,10 @@ import sys
 from pathlib import Path
 
 import pytest
-from vistir.contextmanagers import temp_environ
 
 from pdm.cli import actions
 from pdm.models.requirements import parse_requirement
-from pdm.utils import get_python_version
+from pdm.utils import get_python_version, temp_environ
 
 
 def test_help_option(invoke):
diff --git a/tests/test_project.py b/tests/test_project.py
index ff8f2ecb3898f1a31c56b9985189cc3940d23329..93aed0cd5487fda37405c2c3fd0a62e026fb34c9 100644
--- a/tests/test_project.py
+++ b/tests/test_project.py
@@ -2,9 +2,9 @@ import os
 from pathlib import Path
 
 import pytest
-from vistir import temp_environ
 
 from pdm.project import Project
+from pdm.utils import temp_environ
 
 
 def test_project_python_with_pyenv_support(project, mocker):